Clayton Williams Energy Acquisition - Tables (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
	Apr. 24, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Business Acquisition [Line Items]
Plus: Cash Consideration Paid to Clayton Williams Energy Stockholders				$ 616	$ 0
Goodwill		$ 1,295		1,295		$ 0
Clayton Williams Energy
Business Acquisition [Line Items]
Fair Value of Common Stock Issued	$ 1,876
Plus: Cash Consideration Paid to Clayton Williams Energy Stockholders	637
Total Purchase Price	2,513
Accounts Payable	67
Other Current Liabilities	38
Long-Term Deferred Tax Liability	520
Long-Term Debt	595
Asset Retirement Obligations	58
Total Purchase Price Plus Liabilities Assumed	3,791
Cash and Cash Equivalents	21
Other Current Assets	63
Proved Reserves	722
Undeveloped Leasehold Cost	1,571
Gathering and Processing Assets	48
Asset Retirement Costs	58
Other Noncurrent Assets	13
Goodwill	1,295	1,300		1,300
Total Asset Value	$ 3,791
Revenues		960	$ 964	3,102	2,605
Net Loss and Comprehensive Loss Attributable to Noble Energy		$ (133)	$ (193)	$ (1,561)	$ (860)
Net Loss Attributable to Noble Energy per Common Share - Basic and Diluted ($ per share)		$ (0.27)	$ (0.40)	$ (3.21)	$ (1.77)